Recently, research and development has been intensively carried out on processed foods, nutrition supplements, pharmaceutical compositions and the like taking advantage of functional compositions in food. There are also many studies on the efficacy of koji, which is a fermented product to be processed in traditional Japanese foods such as miso and shoyu, including a study reporting a component derived from koji having an effect of controlling obesity.
For example, Japanese Patent Application Laid-Open (JP-A) No. H07-112937 describes an obesity prevention agent containing rice malt; JP-A No. 2001-145498 describes a composition that has an effect of suppressing fatty liver and contains an extraction of barley malt; and JP-A No. 2012-219077 describes a composition that has an effect of reducing neutral fat and contains a component derived from tea leaves fermented with black rice malt.
Meanwhile, a component that activates peroxisome proliferator-activated receptors (PPARs) has been attracting attention as a component having an effect of controlling obesity. PPARs are part of a nuclear receptor superfamily, and three subtypes of α, γ and δ are known. In particular, PPARα is known to highly express in liver and skeletal muscles, and regulates transcription of target genes being involved in lipid metabolism.
With regard to food containing a component that activates PPARα, solanaceous plants such as tomato or eggplant (see, for example, JP-A No. 2011-184411), fermented products of soybean (see, for example, JP-A No. 2012-171924 and JP-A No. 2008-203209), extracts of acacia balk (see, for example, JP-A No. 2009-203209), fermented products of Monascus purpureus (see, for example, JP-A No. 2011-144172) and the like have been reported.